Your orbital diagram is a little off. The axis should point in the same direction throughout the year.
The axis does rotate a little over very long periods(for Earth I think about 26,000 years). This is called precession. I don't have the formula handy, but off the top of my head, I'd say a precession period approximating the length of a planet's year would be a fairly unphysical phenomenon, at least for habitable planets.
I've made a crappy reworking of your chart to show how the axis of the planet should look as the planet revolves about it's primary.
My writing was unclear. What I meant to say was that the planet has seasons in the same sense as the Earth, but because the axis is at a much larger angle to the equator the seasons are more extreme so that the pole is pointed almost directly away from the sun in winter and almost directly toward the sun in summer.
Another, separate influence is that the planet moves much closer to the sun at one point in its orbit and much further away at the opposite point in its orbit. Because of this the entire planet is considerably warmer at perihelion(the close point), and considerably colder at aphelion(the far point). I had a math teacher who pronounced these as pair-uh-heel-ee-uhn and uh-feel-ee-uhn, but I think the correct pronunciation for the latter is ap-heel-ee-uhn. Anyway.
I'm assuming that perihelion is occurring at the same time as the north pole points away from the sun, because of that the north pole will point away from the sun at aphelion. As you can probably see from the lame chart I made, the northern summer will be warmer because of this eccentricity and the southern winter will be colder. Another effect is that the northern winter will be very short and the southern winter will be very long.
The northern hemisphere will have a long summer varying from quite warm to very cool or cold, this should result in a very long growing season. For earthly plants, this could result in several seasons of growth with plants from very different climates thriving in the same location at different times throughout the year. In the south, the winter may be long enough to create an ice cap which could even be large enough to survive the very hot, but very short summer. How large would a glacier have to be to survive, say, two weeks of constant daylight at 110ºF? Hey Redrobes, you wanna try modelling this?
I've made a terrible chart all my own to try to demonstrate my idea.
Whether you use my idea or not, this is a really fun gedanken experiment that I might try myself.
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